The purpose of this study is to examine the contribution of stressors to drug abuse and dependence, as modified by coping style. Young, low-income women have received inadequate attention in most studies of stress and drug disorder, and these young women are in an age group with increasing drug use and burdens of stress. A prospective cohort study will be conducted to relate increases in stressors to onset of drug disorder, as well as progression of drug use, to abuse and dependence. In this study, a total of 600 12-month drug users (with 311 non-Hispanic white, 103 non-Hispanic black, and 186 Hispanic women) will be interviewed. These detailed interviews will occur in person at baseline, 12, and 24 months. In between the in-person interviews, brief telephone interviews will be conducted every other month. Participants will attend one of 24 state-funded clinics providing gynecological and reproductive services. CAPI methods will be used for each interview. Participants will be asked to provide, in person or by mail, four saliva samples for four cortisol tests and one urine sample for a drug test panel. The primary aims of this proposal are to: (1) study and report the epidemiology of stress exposure, particularly operant stressors (defined as the occurrences and accumulation of recent and ongoing stressors), in young, low-income women over time; (2) understand and examine the relationships of operant stressors with onset of DSM-IV abuse/dependence over time through theory-driven hypotheses (eg, self-medication); (3) examine whether an individual's coping style modify the relationships of different operant stressors with abuse/dependence. Our secondary aims are to (1) to examine the reciprocal effects of drug disorder on stressors; (2) to examine the above relationships by ethnic/racial status. We will conduct a relatively comprehensive but focused investigation of operant stressors in young, low- income women and the relation of stressors to drug disorder in this vulnerable population. Clarifying such relationship should help in the development of targeted, effective preventions and interventions to prevent transitions from drug use to abuse and dependence in adulthood.